1. Field of the Invention
This invention relates to a device for determining whether or not the voltage of a battery used with various instruments, such as photographic cameras, is sufficient for use with the instruments.
2. Description of the Prior Art
When the photographing frame speed is to be increased in the motor drive device of a camera or when slow motion photography is to be effected with a cinecamera, these cameras sometimes require a voltage higher than the commonly used voltage. Usually, such cameras are operated by batteries. It is therefore conceivable to contain two batteries having different nominal voltages in discrete cases and to interchangeably mount each of these cases to an instrument such as a motor drive device or a cinecamera.
Now, in instruments using batteries, it has been a common practice to check to determine whether or not the voltage of the battery is sufficient for the voltage used by the instrument. However, when batteries having different nominal voltages are used by being interchangeably mounted, as described above, the check of battery voltage has heretofore been effected only for one nominal voltage. Therefore, inconveniently, the check could not be effected for the battery of another nominal voltage.